On Mon, Jun 26, 2017 at 01:18:23AM +0100, André Przywara wrote: > On 31/05/17 08:18, Corentin Labbe wrote: > > The dwmac-sun8i is a heavy hacked version of stmmac hardware by > > allwinner. > > In fact the only common part is the descriptor management and the first > > register function. > > Hi, > > I know I am a bit late with this, but while adapting the U-Boot driver > to the new binding I was wondering about the internal PHY detection: > > > So here you seem to deduce the usage of the internal PHY by the PHY > interface specified in the DT (MII = internal, RGMII = external). > I think I raised this question before, but isn't it perfectly legal for > a board to use MII with an external PHY even on those SoCs that feature > an internal PHY? > On the first glance that does not make too much sense, but apart from > not being the correct binding to describe all of the SoCs features I see > two scenarios: > 1) A board vendor might choose to not use the internal PHY because it > has bugs, lacks features (configurability) or has other issues. For > instance I have heard reports that the internal PHY makes the SoC go > rather hot, possibly limiting the CPU frequency. By using an external > MII PHY (which are still cheaper than RGMII PHYs) this can be avoided. > 2) A PHY does not necessarily need to be directly connected to > magnetics. Indeed quite some boards use (RG)MII to connect to a switch > IC or some other network circuitry, for instance fibre connectors. > > So I was wondering if we would need an explicit: > allwinner,use-internal-phy; > boolean DT property to signal the usage of the internal PHY? > Alternatively we could go with the negative version: > allwinner,disable-internal-phy; > > Or what about introducing a new "allwinner,internal-mii-phy" compatible > string for the *PHY* node and use that? > > I just want to avoid that we introduce a binding that causes us > headaches later. I think we can still fix this with a followup patch > before the driver and its binding hit a release kernel. > > Cheers, > Andre. > I just see some patch, where "phy-mode = internal" is valid. I will try to find a way to use it Regards -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
